1. Field of the Invention
The invention relates to a write head for ink printer devices and more particularly to a write head having tubular ink channels which have one end connected to an ink supply system and are in communication at their other end with the discharge openings of nozzle shoe of the write head and which are surrounded over a part of their length by individually drivable small piezo tubes under whose influence a drop-by-drop ejection of ink ensues.
2. Description of the Prior Art
It is known (German Pat. No. 2 543 451) in the construction of write heads for ink printer devices to cast a pre-assembled unit containing forming needles and tubular piezo elements, whereby the ink channels arise in the write head after the removal of the forming needles. The ink channels are closed with a nozzle shoe at their end facing the write location. At the other end of the ink channels, these ink channels are in communication with an ink supply system. The manufacturing outlay connected with such a construction is relatively high and requires a high degree of manual activity. In particular, the observation of extremely tight tolerances raises high demands, this frequently leading to involved after-treatment or reworking of the individual parts.
In order to reduce this outlay, it is also known (German OS No. 3 234 408) to combine the ink channels and the small piezo tubes allocated to them to form what is referred to as a piezo tube group. The ink channels are thereby arranged fan-shaped and, proceeding from a common web, proceed converging toward the front, where they are combined in a front, conical surface. The manufacture of such a piezo tube group is not simple, particularly because of the very narrow division of the ink channels at the front region; further, a considerable outlay is also required for adjusting the small piezo tubes which are also integrated into the unit.